This subproject is one of many research subprojects utilizing the resources provided by a Center grant funded by NIH/NCRR. The subproject and investigator (PI) may have received primary funding from another NIH source, and thus could be represented in other CRISP entries. The institution listed is for the Center, which is not necessarily the institution for the investigator. Participants will be 14 adults between the ages of 20-22 years and 16 teens between the ages of 13-14 years. The scanning session will begin with a sagittal scout for purposes of prescribing subsequent images. Sagittal T1 MPRAGE images will be aquired for coregistration of functional images. Whole brain EPI BOLD images will be acquired in three runs while subjects perform the behavioral task below. An EPI fieldmap will be acquired at the same resolution and slice locations to allow for offline correction of field inhomogeneities. The behavioral combines a go/nogo task with emotionally arousing background images selected from the International Affective Picture System. In this task, letters are presented sequentially in a small box at the center of the computer screen. Subjects are asked to respond as quickly as possible with a button press to every one of a series of letters except for a specific target: an 'X'. The Xs appear on 25% of trials such that participants acquire a prepotent tendency to press and need to actively inhibit their response during nogo trials. The behavioral task consists of three runs of twelve blocks. Responses (press or no press) and reaction times will be recorded using an MRI compatible button box. We anticipate the entire session taking one hour per subject. This estimate includes 15 minutes for equipment setup and positioning of the participant, 11 minutes of structural scanning, 30 minutes of functional scanning and 10 minutes of clean-up and data transfer.